OP-
IF..the tank has a liner...I suggest a few thoughts. First and foremost...the liner does NOT have to be removed ...in its entirety. Simply tumble the tank enough to remove any liner bubbles... the object is to be able to determine corrosion/pitting issues in regards to the visual inspection. As long as the VIP inspector has the ability to examine the possible issue area within the failed liner, he can make a determination in regards to pitting and integrity. The entire liner need NOT be removed. That being said....SS deck screws WILL cut liner....but be prepared to leave it rolling for quite some time lol... I suggest a clean up tumble using a decent semi aggresive ceramic media in order to determine the corrosion under the liner bubbles...once you can SEE the depth of the issue...decide from there. JMO.
Do yourself a favor....get educated. Read, learn, ask questions of KNOWLEDGABLE sources...note I didn't say.."ask questions of your hydro staff".....unfortunately it has been my experiance that MOST..not all...but most...are to a large degree ignorant of the truths regarding steel tanks, and liners. After my second LP72 was failed... WRONGLY.... ( ummm...never heard of a Sustained load cracking issue in STEEL....) and XXXXXX ed out all the markings without asking...and condeming perfectly good tanks...I went the get myself "ed-u-ma-kated" and PSI certified route. Talk about ALOT less hassle....now I KNOW my tanks are good...instead of wondering.
Bubs